cccp

I have been hearing about sraight piping and some people say its good while others say its bad because there is no back compression. I know that it is illegal in some cities and i am not planning on doing it on my car but i am just wondering if straight piping gives more horse power or if staraight piping is no good?

jimbo74

it depends on the situation... and running straight pipe on any vehicle isnt illegal in cities, but is illegal anywhere in the US... its a federal violation to remove a catalytic convertor on a vehicle equipped with one and it will also cause problems with the ECM

rimpainter.com

Yep, it depends on the vehicle and situation. For example, straight pipe an EVO or Subie turbo, and you are likely to see some significant gains (assuming you can keep the ECU from freaking out during boost spike). I bought a Celica All Trac Turbo a while back, and the previous owner gutted the cat. I went and had a Car Sound cat installed, and I could feel the difference in power (loss). So it does make a difference on some vehicles, even in stock form. However, if you straight pipe a vehicle that was never intended to have open exhaust (or no cat), you could run into a host of issues. I lost all my low-end torque back in my racer days when I put a straight pipe on my Mazda truck. The thing was much faster with a cat on, and a much better daily driver. I did the same thing on my 95 Civic SI and it really didn't do anything except get louder. So, I was spewing more fumes into the air for no reason.

On a track vehicle with the right tuning equipment, straight-piping is a good mod. Otherwise it is just plain stupid.

hamstrungtaco

sounds like ÅÅÅÅ in a 2.7 with a header and flowmaster super 40, dont try that

Randomness

When you say straightpiping, are you talking about removing the cat? I've always heard of straightpiping as no mufflers, and possibly no cat either. In which case it's painfully loud, and unless you have a nice V8, you'll just sound like a fishing boat with an outboard motor.

ThomasJ

I just got new exhaust on my 2nd gen 3.0 4Runner. The old pipe rusted out just behind the cat and broke off. I drove around all weekend like this and it felt like it lost about 20hp. not to mention it sounded like ÅÅÅÅ. when i got the new exhaust on the power came right back.

I also have a SVO Mustang (turbocharged) and it loves free flowing exhaust. The less backpressure the better on a turbo engine. Its not uncommon for a turbo car to gain upwards of 20hp just from free flowing exhaust.

89macrunner

I had a dream the other night where i got in an accident (not my fault) but for some reason or another my exhaust from the crossover back gut cutt off.....i remeber in the dream my truck had NO low end power so i would go nowhere till i reved it up to 3 grand....LMAO

anyways straight pipes would be a bad move on our trucks, not only are you doing something illegal but you are sacraficing all your torque. Your truck would be LOUD and sound terrible......... ive heard my truck without a cat before and ill tell ya..it was loud but by no means sounded cool...i can imainge it would just keep sounding worse if you have pipes all the way to the back...

I have a glasspack now and i get TONs of burbuling and farting from the pipe..sounds pretty good for a v6 tho

cccp

Well i am not planning on tacking off my muffler at all. I was just wondering if it gave you more horse power or not.

2001Millrunner

with everything said above, smell will kill you before the cops will..........it stinks and you will not have fun washing the nasty,black, tarry stuff off your rear bumper or anything around exhaust tip. On my old prelude all it did was gain a tiny bit at high RPM but lost a whole lotta TQ at low end. Straignt pipe=bad